Research On Synthesis And Compound Modification Of Poly Methyl Ester Pour Point Depressant For Lubricating Oil

Pour point depressant is a lubricating oil additive which can effectively enhance lubricating oil flow property at low-temperature, having a strong selectivity to lubricating oil. So it is difficult for a single pour point depressant to apply to different lubricating oil. In order to meet the real needs, we need to study on the compound modification of pour point depressant, realizing the good susceptibility to various lubricating oil, thus, the performance and economy of pour point depressant were increased.This paper mainly studied the synthesis and compound modification of poly methyl ester pour point depressant for lubricating oil. First, methyl acrylic acid high carbon ester was prepared by the method of solvent esterification. Take the synthesis of tetradecyl methyl acrylate as an example, the conditions of esterification reaction were obtained by single factor experiment and four factors three levels orthogonal experiment method. The molar ratio of acid and alcohol was 2.0, the amount of catalyst and inhibitor were 1.2% and 0.7% respectively ?percentage of total mass of reactants?, the reaction time was 5 h, the reaction temperature was 140?. Then we synthesized a series of binary copolymer poly methyl acrylic acid high carbon ester -maleic anhydride ?AmM?, the binary copolymer poly methyl acrylic acid high carbon ester-vinyl acetate ?AmV?, and the terpolymer poly methyl acrylic acid high carbon ester-maleic anhydride-vinyl acetate ?AMV?. The conditions of polymerization reaction were obtained by single factor experiment with viscosity and effect of pour point depressant as index. The optimal polymerization were:temperature was 80?, monomer ratio was 3:1:1, initiator addition was 1.0%, reaction time was 6 h.We screened the pour point depressant with the best depressive effect from the synthetic ones to investigate the compound and modification. One part was compounding binary copolymer ?AmM, and AmV? to prepare compounded pour point depressant. When the compounding ratio were m_AmV14:m_AmV16=2:1, m_AmM14:m_AmM16=1:1, m_AmV14:m_AmM14= 2:1 respectively, three prepared compounded pour point depressants can decrease the pour point of base oil by 8.3?,8.5?,9.8?, whose depressive effect was higher than the single pour point depressant. Moreover, the additive conditions on depressive effect were studied, the best additive conditions were:the dose plus was 1.0%, temperature was 60?, the cooling rate was 0.6?/min. Another part were treating terpolymer with alkyl amine of different carbon chain lengths and modifying the terpolymer to prepare aminolysis pour point depressant. Selected terpolymer with mixed amine had the best depressive effect, and the product was characterized by IR. Before and after the aminolysis of the terpolymer, the depressive effect were compared and analyzed, it can be found that the terpolymer after aminolysis exhibited better susceptibility to base oil, and paraffin base oil showed the largest flow rate.